The technology described herein relates generally to electronic alert devices and more particularly to electronic alert devices that communicate with a host device, such as a cellular telephone, to provide an alert about an event or other action at the host device.
Cellular telephones, smartphones, tablet computers, wireless communication devices, etc. often use an audible signal, such as a ring tone, to indicate an incoming voice phone call or incoming text (Short Message Service or SMS) message or incoming email. These audible tones can be annoying in some cases (e.g. the ring tone occurs in a quiet concert hall) or can be difficult to hear in other cases (e.g., the tone occurs in a noisy restaurant or bar, etc.). In these cases, it is often desirable to use a vibratory alert device that can be worn closely on a user such that the vibratory alert device is close to or touching the user's skin. Vibrations from such a device can be felt by the user but can also be relatively quiet such that, from a sufficient distance from the user, the vibrations are not audible to others (or perhaps even to the user). Thus, vibratory alert devices can provide a relatively quiet alert to the user whether the user is in an environment that requires silence or is in a very noisy environment. Also, the vibratory alert device can be used in those situations in which the cellular telephone, or other device that is paired with the vibratory alert device, cannot be kept near the user (e.g., the cellular telephone or other device is in the user's purse or briefcase or backpack, etc.).
One example of a class of vibratory alert devices is the recently developed smartwatch which is an accessory of a smartphone, such as an iPhone; the smartwatch is paired to work, through Bluetooth Low Energy wireless communication, with the smartphone and provides vibratory alerts and includes a sophisticated touch based user interface that is displayed on a display device of the smartwatch. The touch screen on these types of devices is one of several input devices as they often include multiple buttons for a user to press to control or configure the smartwatch. These smartwatches are complicated and large and are worn on a user's wrist. U.S. Pat. No. 8,421,607 provides another example of a vibratory alert device.